Krystina Cassidy and Dianna Simpson attempt to make contact with their husbands who are stationed inside Fort Hood, while standing outside of the Bernie Beck Gate, on Wednesday, April 2, 2014.

An Iraq veteran fatally shot three soldiers and himself at Fort Hood in Texas, where a rogue officer killed 13 people in 2009, said Lieutenant General Mark Milley, the U.S. Army base’s commander.

The soldier, who was being evaluated for post-traumatic stress disorder, killed himself with a .45-caliber Smith & Wesson pistol as police approached, Milley said. He was identified as Specialist Ivan Lopez by a U.S. official who asked for anonymity because the name hasn’t been officially released. Sixteen people were hurt in the attack, which happened just after 4 p.m. local time yesterday, Milley said.

“We do not know a motive,” Milley said. “He had behavioral health and mental health issues and was being treated for that.”

Investigators believe the shooter walked into a building in a medical area, opened fire, entered another building and shot again, Milley said. When a military police officer approached the attacker in a parking lot, the man put the gun to his head, the general said.

The shooter served four months in Iraq in 2011 and reported a brain injury, Milley said. He declined to identify the gunman because his family hadn’t been notified.

Glen Couchman, chief medical officer at Baylor Scott & White Health Central Texas, said in a televised news conference that victims at the Temple hospital suffered wounds to the neck, chest, abdomen and extremities. The conditions ranged from stable to “quite critical,” he said.

War’s damage

President Barack Obama was briefed in a conference call with Defense Secretary Chuck Hagel and top military leaders, according to a White House statement. The president directed that “every resource available” be used in the shooting probe and appointed the Defense Department to lead the investigation.

“We are going to get to the bottom of exactly what happened,” Obama told reporters in Chicago, where he was attending a fundraiser for the Democratic National Committee.

About 20 percent of returning veterans will have post-traumatic stress disorder and another 20 percent traumatic brain injury, according to Hannah Rudstam, a Cornell University researcher who has studied their reintegration. In 2012, then-Defense Secretary Leon Panetta said the military should improve its diagnoses.

“These are real problems,” he told a Senate committee. “It’s unacceptable now to have the process we have in place.”

Second slaughter

The shooting was the second at a major U.S. military base since September, when Aaron Alexis, a former Navy reservist who believed he was under the control of extremely low frequency electromagnetic waves killed 12 people at the Washington Navy Yard.

Fort Hood, about 60 miles (97 kilometers) north of Austin, houses about 41,000 troops and is home to the Army’s 1st Cavalry and 4th Infantry divisions.

In 2009, the base was the scene of a shooting in which an Army psychiatrist, Major Nidal Hasan, killed 13 people and wounded more than 30. Hasan, who had become radicalized by an al-Qaeda terrorist based in Yemen, attacked while yelling “Allahu Akbar,” Arabic for God is Great.

The gunman, who later said he took aim at the soldiers because he viewed them as a threat to Taliban leaders in Afghanistan, was sentenced to death by a military court.

“Any time you lose any of your people to these kinds of tragedies there’s a problem,” Hagel said in Honolulu. “We don’t have a choice here but to address these and do everything possible to assure the safety of our men and women. And it’s not a challenge too tough to address.”